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147 Uppsatser om Nutrients - Sida 3 av 10
Analys av framtidens system för hantering av avloppsvatten och matavfall i Eskilstuna
Wastewater treatment is increasingly controlled by the Swedish environmental quality objectives, adopted by the Swedish parliament. There is a need for a sewage system that can fulfill stringent requirements concerning the environment, recycling and resource use and hygiene. Additional environmental aspects in recent years are the impact of climate change, new knowledge about the effects of pharmaceuticals in water, the need for improved wastewater treatment and increased recycling of Nutrients to agriculture. This report has, from a future scenario of the year 2050, analyzed seven different systems for wastewater treatment and treatment of compostable biowaste from households in Eskilstuna. A future scenario was chosen based on that within a forty year period new challenges may arise which can result in higher demands on sewage treatment than those we see today. Another reason why the future scenario was established is that changes in wastewater treatment systems are slow to establish. The analysis is mainly focused on the economical aspects but environmental aspects such as emissions to receiving waters and potential recycling of plant Nutrients has also been evaluated briefly.
Lillån : Statusbedömning enligt EU:s ramdirektiv för vatten
In Sweden, the County Administration board is responsible for improving the water quality in lakes and watercourses according to the European Union Water Framework Directive. In Västmanland county, where river Lillån is situated, the County Administration of Västmanland have the main responsibility for the aquatic environment in that area. The knowledge about the different watercourses in the chatchment of river Lillån is today limited. The aim with this study was to evaluate the ecological quality of River Lillån based on water chemistry analyses and benthic fauna investigations. The aim was also for the benthic fauna to compere different samplingsites and sampling methods with each other in order to see how the species composition changes in the river, and to see the advantages and disadvantages with different sampling tecniques.
Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm
In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.
Näringsretention i återskapad våtmark på betesmark : studier av en mad vid Bornsjön
It is important to construct or recreate different types of wetlands and study their retention of Nutrients, since knowledge of their effectiveness in this matter is poor. In 2003 a wetland was constructed on an old meadow on the western shore of Lake Bornsjön in central Sweden. The main purpose of the wetland was to reduce the amount of phosphorus entering the lake, which is the back-up water supply for Stockholm when the city cannot obtain water from Lake Mälaren. Large areas around Lake Bornsjön consist of agricultural land and the nutrient concentrations in the inflows to the lake are usually relatively high (approx. 1 mg/l total nitrogen and 0.05-0.1 mg/l total phosphorus).
Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter
This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The Nutrients will then be recirculated to arable land through residues from biogas production. The amount of Nutrients that can be removed by harvesting the biomass
depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet
grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts.
Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance.
This literature has illuminated a major environmental problem and it has been suggested
optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a
definite answer for the optimal method for each site tests should be carried out, this because many
factors determine to what is suitable for each, specific environment.
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Safe retrieval of nutrients to improve food security
Safe retrieval of Nutrients from human excreta to fertilize crops in order to gain adequate yields will increase food security and sustainability in agriculture areas with nutrient-poor fields. Safe and nutritious food will meet the dietary needs of the individual which promotes public health and the ability of an active life. Human excreta should be considered as a resource instead of being assumed as waste. Human faeces and urine is excellent fertilizers which may close the nutrient loop if utilized properly. However, sanitation of the excreta is required to prevent disease transmission by reducing the content of gastrointestinal pathogens such as bacteria, viruses and parasites.
The objective of this study was to in small scale evaluate the sanitation in a combined liquid compost and urea treatment by monitor the inactivation of bacteria and viruses at the combination three start temperatures, 45, 40 and 35 °C, and three additions of urea, 0.5, 0.75 and 1 % and reference, 0 % urea addition.
En studie av retentionen i floden Oder och dess avrinningsområden, Polen.
Nutrient enrichment is the main cause of the increasing eutrophication process in the Baltic Sea during last century. A prerequisite counteract this process the load of Nutrients to the Sea must be investigated. The large contribution of Nutrients to the Sea is caused by emission from the rivers within the drainage basin. For the total emission of nutrient into the Sea the retention process in the rivers has big influence. This process in the river system has been assumed as a not important part of the nutrient cycle.
Användning av rötrest från kombinerad etanol och biogasproduktion : en jämförelse mellan tre alternativ
Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by
Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer
(system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in
terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.
Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering
Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, Nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of Nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.
En guide i näringslära och utfodring vid några vanliga sjukdomstillstånd hos hund och katt :
This report describes the nutritional requirements of the dog and cat. You are also able to learn about the most common diseases in the dog and cat where food has an important role in both prevention and recovery of these diseases. We describe FLUTD, canine urolithiasis, heart- and kidney disease, gastrointestinal diseases and obesity. You have to know the right balance between different Nutrients to decrease the stress on the body and to prevent the advancement of the diseases. Finally we discuss the differences between three manufacturers of veterinary prescribed diets and two commercial pet foods..
Jordbrukets påverkan på Östersjön : en jämförelse av indikatorer för att beskriva näringsbelastningen
The Baltic Sea, due to its special conditions, is a unique and vulnerable marine environment. There are many pressures that have an impact on the sea and one of the major problems is the extensive flow of Nutrients from land. The most visible effect of the supply of Nutrients is the annual algal blooms.
One of the main sources of nitrogen and phosphorus supply is agriculture. Nutrient losses
from arable land have been increasing as agricultural production has intensified. At the end of the twentieth century an increased awareness of these problems led to the formation of organizations such as HELCOM and Baltic 21.
Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys
This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.
Referensvåtmarker för uppföljning av växtnäringsretention i anlagda våtmarker
One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by Nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of Nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove Nutrients.
Utvärdering av Naturvårdsverkets bedömningsgrunder för makrofyter i sjöar
According to the Water Framework Directive of the European Union, macrophytes should be used as indicators in the ecological and environmental monitoring of lakes. In the member state Sweden the Environmental Protection Agency has elaborated assessment criteria for determining lake status based on macrophytes. The main focus of this thesis is to evaluate the efficiency of the assessment criteria for macrophytes. In addition the concordance between the ecological status classes of the four quality factors included was analysed.The assessment criteria for macrophytes are based on the total phosphorus preference of the respective species. The focus is thus mainly on the nutrient level of the investigated lakes and the environmental problem monitored is eutrophication.
Näringsbelastning på en anlagd våtmark från åker, skog och enskilda avlopp :
This work is a part of the project ?Våtmarker i odlingslandskapet ? uppföljning av miljömålen? (Wetlands in arable land ? following-up of the environmental goals). The main objective with this project is to study nitrogen and phosphorus retention in a constructed wetland by using mass balance calculations. Continuous measurements of Nutrients and water flow through the inlet and the outlet of the wetland are made. However, substantial amounts of nitrogen and phosphorus were assumed to reach the wetland with a drain-pipe transporting wastewater from nearby houses (10 persons).